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salivary glands

(Encyclopedia)salivary glands sălˈəvârˌē [key], in humans, three pairs of glands that secrete the alkaline digestive fluid, saliva, into the mouth. Most animals have salivary glands that resemble those in hum...

wax

(Encyclopedia)wax, substance secreted by glands on the abdomen of the bee and known commonly as beeswax; also various substances resembling beeswax. Waxes are mixtures comprising chiefly esters of monohydroxy alcoh...

spontaneous combustion

(Encyclopedia)spontaneous combustion, phenomenon in which a substance unexpectedly bursts into flame without apparent cause. In ordinary combustion, a substance is deliberately heated to its ignition point to make ...

polarization of light

(Encyclopedia)polarization of light, orientation of the vibration pattern of light waves in a singular plane. Unpolarized light can be converted into a single polarized beam by means of the Nicol prism, a device ...

specific gravity

(Encyclopedia)specific gravity, ratio of the weight of a given volume of a substance to the weight of an equal volume of some reference substance, or, equivalently, the ratio of the masses of equal volumes of the t...

metabolite

(Encyclopedia)metabolite, organic compound that is a starting material in, an intermediate in, or an end product of metabolism. Starting materials are substances, usually small and of simple structure, absorbed by ...

ink

(Encyclopedia)ink, pigmented fluid used for writing and drawing, or a viscous compound used for printing, both of various colors but most frequently black. The oldest known variety, India ink or China ink, is still...

collagen

(Encyclopedia)collagen kŏlˈəjən [key], any of a group of proteins found in skin, ligaments, tendons, bone and cartilage, and other connective tissue. Cells called fibroblasts form the various fibers in connecti...

candle, cylinder of wax or tallow

(Encyclopedia)candle, cylinder of wax or tallow containing a wick, used for illumination or for ceremonial purposes. The evidence of ancient writings is not conclusive as to the history of the candle; words transla...

charcoal

(Encyclopedia)charcoal, substance obtained by partial burning or carbonization (destructive distillation) of organic material. It is largely pure carbon. The entry of air during the carbonization process is control...